Headphone



FIG. 1 is a front perspective view of a headphone showing the new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a side elevational view thereof;

FIG. 5 is an opposite side elevational view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines illustrate portions of the headphone that form no part of the claimed design. 

CLAIM The ornamental design for a headphone, as shown and described. 